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Chinese Journal of Chemical engineering 2021年第11期34卷 112-125页

作者： Abdullah A.Basaleh Muhammad H.Al-Malack Tawfik A.Saleh department of civil and Environmental engineering King Fahd University of Petroleum and MineralDhahran 31261Saudi Arabia department of Chemistry King Fahd University of Petroleum and MineralDhahran 31261Saudi Arabia

In this research,polyamide modified baghouse dust nanocomposite(PMBHD)was synthesized from steel industry waste using the interfacial polymerization *** capacities of the PMBHD were examined for the uptake of cadmium Cd(Ⅱ),lead Pb(Ⅱ),and methylene blue MB from simulated *** effects of different operational factors of the adsorption,including contact time,pH,adsorbent dosage,initial concentration,and temperature,were *** obtained results revealed that the equilibrium data of MB,Pb(Ⅱ),and Cd(Ⅱ)were best fitted to Dubinin-Radushkevich,Langmuir,and Freundlich *** removal uptake was found to be 6.08,119,and 234 mg·g^(-1),whereas maximum removal efficiencies of 90%,99.8%,and 98%were achieved for MB,Pb(Ⅱ),and Cd(Ⅱ).Adsorption kinetics of MB and metals well-fitted to the pseudo-second-order *** characterization results showed the presence of polymeric chain on the surface of the *** thermodynamic study revealed that the values of the free energy DG for Pb(Ⅱ)and Cd(Ⅱ)were found to be negative,which indicates spontaneous,energetic,and favorable *** for MB removal,positive values of(DG)were noticed,which implies that the adsorption was *** proposed mechanism for the adsorption of MB and metals on the PMBHD showed that the dominating mechanism is *** adsorption/desorption results verified the high reusability of the PMBHD for adsorption of MB and metals.

关键词： Waste management Adsorption Low-cost adsorbents Nanomaterials Polymerization Composites

The mechanical and water absorption properties of carbon fiber buoyancy materials under hydrostatic pressure

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Science China Technological Sciences 2025年第1期 251-265页

作者： Fanglin CONG Zihan LI Guocai YU Yang JIN Zixu ZHU Linzhi WU College of Aerospace and civil engineering Harbin Engineering University Key Laboratory of Advanced Ship Materials and Mechanics Harbin Engineering University department of Basic Courses Naval University of Engineering

Buoyancy material technology is of paramount importance for the development of marine engineering. In this study,a novel carbon fiber buoyancy material(CFBM) is designed and prepared by utilizing composite circular tubes with light weight and high strength. To reveal the failure mechanism under hydrostatic pressure, a finite element model(FEM) based on the three-dimensional Hashin and Yeh failure criterion is developed and validated experimentally. Both the simulated and experimental results indicate that the hydrostatic strength of the CFBM is mainly determined by the buckling of carbon fiber tubes located at the edges of the CFBM. Parametric analysis is conducted to investigate the effect of the number of unit-cells,length, and wall thickness of carbon fiber tubes on the mechanical properties of the CFBM. In addition, a 60-day water absorption test of the CFBM at 12.5 MPa is conducted to characterize its durability. Experimental results indicate that the maximum water absorption rate of the CFBM is 0.59% and the hydrostatic strength is reduced by only 7.97% during the 60-day test period. Finally, the designed CFBM is used at the water depth of 1000 m as buoyancy material. Compared with traditional buoyancy materials, the proposed CFBM has significant advantages in both hydrostatic strength and density. This work has broad engineering application prospects and is of high significance for promoting the implementation of carbon fiber composites in the ocean engineering field.

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Semi-active model predictive control for 3rd generation benchmark problem using smart dampers

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Earthquake engineering and engineering Vibration 2007年第3期6卷 307-315页

作者：颜桂云孙炳楠吕艳平 department of civil engineering Fujian University of Technology department of civil engineering Zhejiang University department of civil engineering Fuzhou University

A semi-active strategy for model predictive control （MPC）, in which magneto-rheological dampers are used as an actuator, is presented for use in reducing the nonlinear seismic response of high-rise buildings. A multi-step predictive model is developed to estimate the seismic performance of high-rise buildings, taking into account of the effects of nonlinearity, time-variability, model mismatching, and disturbances and uncertainty of controlled system parameters by the predicted error feedback in the multi-step predictive model. Based on the predictive model, a Kalman-Bucy observer suitable for semi-active strategy is proposed to estimate the state vector from the acceleration and semi-active control force feedback. The main advantage of the proposed strategy is its inherent stability, simplicity, on-line real-time operation, and the ability to handle nonlinearity, uncertainty, and time-variability properties of structures. Numerical simulation of the nonlinear seismic responses of a controlled 20-story benchmark building is carried out, and the simulation results are compared to those of other control systems. The results show that the developed semi-active strategy can efficiently reduce the nonlinear seismic response of high-rise buildings.

关键词： nonlinear seismic response model predictive control semi-active strategy benchmark problem magnetorheological damper

A two-dimensional limit equilibrium computer code for analysis of complex toppling slope failures

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Journal of Rock Mechanics and Geotechnical engineering 2021年第1期13卷 114-130页

作者： Akbar Ardestani Mehdi Amini Kamran Esmaeili School of Mining engineering College of EngineeringUniversity of TehranTehranIran department of civil and mineral engineering University of TorontoTorontoOntarioCanada

Evaluation of blocky or layered rock slopes against toppling failures has remained of great concern for engineers in various rock mechanics *** step-by-step analytical solutions have been developed for analyzing these types of slope ***,manual application of these analytical solutions for real case studies can be time-consuming,complicated,and in certain cases even *** study will first examine existing methods for toppling failure analyses that are reviewed,modified and generalized to consider the effects of a wide range of external and dead loads on slope ***,based on the generalized presented formulae,a Windows form computer code is programmed using Visual C#for analysis of common types of toppling *** parameters,including slope geometry,joint sets parameters,rock and soil properties,ground water level,dynamic loads,support anchor loads as well as magnitudes and forms of external forces,are first loaded into the *** input data are then saved and used to graphically draw the slope *** is followed by automatic identification of the toppling failure mode and a deterministic analysis of the slope stability against this failure *** results are presented using a graphical *** developed code allows probabilistic introduction of the input parameters via probability distribution functions(PDFs)and thus a probabilistic analysis of the toppling failure modes using Monte-Carlo simulation *** allows calculation of the probability of slope ***,several published case studies and typical examples are analyzed with the developed *** outcomes are compared with those of the main references to assess the performance and robustness of the developed computer *** comparisons demonstrate good agreement between the results.

关键词： Rock slope Toppling failures Analytical solution Windows form application Deterministic analysis Probabilistic analysis

Kinetics of hydrogen peroxide quenching following UV/H_(2)O_(2)advanced oxidation by thiosulfate,bisulfite,and chlorine in drinking water treatment

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Frontiers of Environmental Science & engineering 2023年第12期17卷 59-69页

作者： Tianyi Chen Lizbeth Taylor-Edmonds Susan Andrews Ron Hofmann department of civil and mineral engineering University of TorontoTorontoOntario M5S 1A4Canada

Residual H_(2)O_(2)from UV/H_(2)O_(2)treatment can be quenched by thiosulfate,bisulfite,and chlorine,but the kinetics of these reactions have not been reported under the full range of practical *** this study,the rates of H_(2)O_(2)quenching by these compounds were compared in different water matrices,temperatures,pH,and when using different forms of bisulfite and *** general,it was confirmed that thiosulfate would be too slow to serve as a quenching agent in most practical *** pH 7-8.5,chlorine tends to quench H_(2)O_(2)more than 20 times faster than bisulfite in the various conditions *** important observation was that in lightly-buffered water(e.g.,alkalinity of 20 mg/L as CaCO_(3)),the form of chlorine can have a large impact on quenching rate,with gaseous chlorine slowing the reaction due to its lowering of the pH,and hypochlorite having the opposite *** impacts will become less significant when water buffer capacity(i.e.,alkalinity)increases(e.g.,to 80 mg/L as CaCO_(3)).In addition,water temperature should be considered as the time required to quench H_(2)O_(2)by chlorine at 4℃is up to 3 times longer than at 20℃.

关键词： UV/H_(2)O_(2) H_(2)O_(2) quenching Chlorine type Water alkalinity Temperature

Experimental study on microstructural and corrosion behaviors of friction stir processed steel with CoCrFeCuTi HEA reinforcement and effect of annealing

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Science China Technological Sciences 2025年第1期 233-250页

作者： S.Aravind KRISHNA N.RADHIKA Alokesh PRAMANIK N.JEYAPRAKASH department of Mechanical engineering Amrita School of EngineeringAmrita Vishwa Vidyapeetham School of civil and Mechanical engineering Curtin University School of Mechanical and Electrical engineering China University of Mining and Technology

The ability to perform against extreme corrosion environments in stainless steel depreciates under challenging conditions in industrial applications. This can be resolved by employing surface modification techniques to modify the surface with the required characteristics. The present study investigates the outcomes of friction stir processing of SS304 with CoCrFeCuTi high entropy alloy(HEA) as reinforcement and the property enhancements post-annealing. The synthesized CoCrFeCuTi HEA exhibited irregular fragments with 17 μm mean particle size and body centred cubic(BCC) phase. The microstructure of the processed surface revealed ultra-refined grains with a uniform distribution of HEA filler. The microstructures of the samples annealed at 400℃, 550℃, 700℃ and 850℃ for 2 h also showed significant grain growth and grain refinements. The processed sample with HEA reinforcement annealed at 700℃ exhibited enhanced microhardness and tensile strength by 63% and 0.88 times than that of the processed sample with HEA pre-annealing. The subsequent electrochemical corrosion test displayed better corrosion resistance for the HEA-processed and annealed sample. Hot corrosion tests at 900℃ showcased excellent resistance for the HEA processed and annealed samples by 14.92%, 12.75%, and 14.83% against the samples pre-annealed under three different salt mixtures, and the corroded surface was analyzed.

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RF Optimizer Model for Predicting Compressive Strength of Recycled Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 215-223页

作者：刘琳王柳燕 WANG Hui SUN Huayue School of civil engineering and Architecture Shenyang University

Traditional machine learning （ML） encounters the challenge of parameter adjustment when predicting the compressive strength of reclaimed *** address this issue,we introduce two optimized hybrid models:the Bayesian optimization model （B-RF） and the optimal model （Stacking model）.These models are applied to a data set comprising 438 observations with five input variables,with the aim of predicting the compressive strength of reclaimed ***,we evaluate the performance of the optimized models in comparison to traditional machine learning models,such as support vector regression （SVR）,decision tree （DT）,and random forest （RF）.The results reveal that the Stacking model exhibits superior predictive performance,with evaluation indices including R2=0.825,MAE=2.818 and MSE=14.265,surpassing the traditional ***,we also performed a characteristic importance analysis on the input variables,and we concluded that cement had the greatest influence on the compressive strength of reclaimed concrete,followed by water. Therefore,the Stacking model can be recommended as a compressive strength prediction tool to partially replace laboratory compressive strength testing,resulting in time and cost savings.

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Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 224-231页

作者：吴宇轩徐文远 YU Tianlai JI Yongcheng School of civil engineering Northeast Forestry University

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1% concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

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Predicting vehicle fuel consumption patterns using floating vehicle data

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Journal of Environmental Sciences 2017年第9期29卷 24-29页

作者： Yiman Du Jianping Wu Senyan Yang Liutong Zhou department of civil engineering Tsinghua University department of civil engineering Columbia University

The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were *** fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers＇ information and vehicles＇ parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed *** fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model.

关键词： Vehicle fuel consumption Prediction Floating vehicle data

Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 49-64页

作者：汪鑫 SHEN Dejian TAO Sijie LIU Ruixin WU Shengxing College of civil and Transportation engineering Hohai University

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate （C3S）.The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

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